Gravity-assisted fluid pump

ABSTRACT

A gravity-assisted fluid pump includes a fluid reservoir, a piston, a valve element, a piston operator, and a valve operator. The piston is movably disposed within the fluid reservoir and is movable between an uppermost position and a lowermost position. The valve element is movable between a closed position and an open position. The piston operator moves the piston between the uppermost position and the lowermost position. The valve operator selectively moves the valve element between the closed position and an open position.

TECHNICAL FIELD

The present invention generally relates to fluid pumps and, more particularly, to a fluid pump in which the pumping action is assisted by the force of gravity.

BACKGROUND

Fluid pumps are used in myriad systems and environments to move various fluids. There are also numerous and varied classes of pumps, such as centrifugal and positive displacement pumps, and numerous and varied pump types within each pump classification. No matter the specific pump classification or type, most are driven by a relatively inefficient prime mover. Moreover, the efficiencies of most pumps is relatively low.

In the present global energy landscape, in which energy resources are becoming more and more scarce, and energy efficiency is becoming more and more pronounced, there is an increased need for a fluid pump that is relatively more energy efficient that presently known pumps. The present invention addresses at least this need.

BRIEF SUMMARY

In one embodiment, and by way of example only, a fluid pump includes a fluid reservoir, a piston, a valve element, a piston operator, and a valve operator. The fluid reservoir includes an inner surface that defines a fluid volume for receiving a fluid. The piston is movably disposed within the fluid reservoir against the inner surface, and divides the fluid volume into an upper variable fluid volume and a lower variable fluid volume. The piston is movable between an uppermost position and a lowermost position and includes an upper side exposed to the upper variable fluid volume, a lower side exposed to the lower variable fluid volume, and an aperture extending between the upper and lower sides. The valve element is movable between a closed position, in which the valve element seals the aperture to thereby fluidly isolate the upper variable fluid volume from the lower variable fluid volume, and an open position, in which the valve element does not seal the aperture to thereby fluidly communicate the upper variable fluid volume with the lower variable fluid volume. The piston operator is coupled to the piston and is responsive to an input force to move the piston to the uppermost position and the lowermost position. The valve operator is coupled to the valve element and is operable to selectively move the valve element to the closed position and an open position.

In another exemplary embodiment, a fluid pump system includes a fluid reservoir, a piston, a valve element, a piston operator, a valve operator, a piston actuator, a valve actuator, and a valve actuator control. The fluid reservoir includes an inner surface that defines a fluid volume for receiving a fluid. The piston is movably disposed within the fluid reservoir against the inner surface and divides the fluid volume into an upper variable fluid volume and a lower variable fluid volume. The piston is movable between an uppermost position and a lowermost position and includes an upper side exposed to the upper variable fluid volume, a lower side exposed to the lower variable fluid volume, and an aperture extending between the upper and lower sides. The valve element is movable between a closed position, in which the valve element seals the aperture to thereby fluidly isolate the upper variable fluid volume from the lower variable fluid volume, and an open position, in which the valve element does not seal the aperture to thereby fluidly communicate the upper variable fluid volume with the lower variable fluid volume. The piston operator is coupled to the piston and is responsive to an input force to move the piston to the uppermost position and the lowermost position. The valve operator is coupled to the valve element and is operable to selectively move the valve element to the closed position and an open position. The piston actuator is coupled to the piston operator and is operable to selectively supply the input force thereto that moves the piston to the uppermost position and the lowermost position. The valve actuator is adapted to receive actuator control signals and is operable, in response thereto, to selectively supply an actuation force to the valve operator to move the valve element to the closed position and an open position. The valve actuator control is operable to supply the actuator control signals to the valve actuator. The valve actuator control is configured to supply actuator control signals that cause the valve element to be moved to the open position when the piston is in the lowermost position, and to the closed position when the piston is in the uppermost position.

In yet a further exemplary embodiment, a fluid pump includes a fluid reservoir, a piston, a valve element, a piston rod, a valve operator, a piston actuator, a valve actuator, and a discharge conduit. The fluid reservoir includes a fluid inlet, a fluid outlet, and an inner surface that defines a fluid volume for receiving fluid. The piston is movably disposed within the fluid reservoir against the inner surface and divides the fluid volume into an upper variable fluid volume and a lower variable fluid volume. The piston is movable between an uppermost position and a lowermost position and includes an upper side exposed to the upper variable fluid volume, a lower side exposed to the lower variable fluid volume, and an aperture extending between the upper and lower sides. The valve element is movable between a closed position, in which the valve element seals the aperture to thereby fluidly isolate the upper variable fluid volume from the lower variable fluid volume, and an open position, in which the valve element does not seal the aperture to thereby fluidly communicate the upper variable fluid volume with the lower variable fluid volume. The piston rod is coupled to the piston upper surface and extends upwardly therefrom to an upper end. The piston operator is responsive to an input force to move the piston to the uppermost position and the lowermost position. The valve operator is coupled to the valve element. The piston actuator is coupled to the piston operator and is operable to selectively supply the input force thereto that moves the piston to the uppermost position and the lowermost position. The valve actuator is coupled to the valve operator and is operable to selectively supply an actuation force thereto that moves the valve element to the closed position and an open position. The discharge conduit has an inlet and an outlet. The discharge conduit inlet is in fluid communication with the lower variable fluid volume via the fluid reservoir fluid outlet, and the discharge conduit outlet is disposed at a position above the upper variable fluid volume.

Other desirable features and characteristics of the fluid pump will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the preceding background.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and wherein:

FIG. 1 is depicts a fluid pump system according to an embodiment of the present invention, with an exemplary embodiment of a fluid pump shown partially in cross-section;

FIGS. 2 and 3 depict cross-section views of portions of the exemplary fluid pump depicted in FIG. 1;

FIGS. 4-7 depict partial cross-section views of the fluid pump depicted in FIG. 1, and illustrate the operation of the exemplary fluid pump; and

FIG. 8 depicts an exemplary alternative configuration of the fluid pump system of FIG. 1.

DETAILED DESCRIPTION

The following detailed description is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. Furthermore, there is no intention to be bound by any theory presented in the preceding background or the following detailed description.

Referring first to FIG. 1, an exemplary embodiment of a fluid pump system 100 is depicted and includes a fluid pump 102 and a pump control 104. The fluid pump 102 is controlled via the pump control 104, and includes a fluid reservoir 106, a piston 108, a valve element 112, a piston operator 114, and a valve operator 116. The fluid reservoir 106 includes an inner surface 118 that defines a fluid volume 122 for receiving a fluid 124. The fluid reservoir 106 additionally includes a fluid inlet 126 and a fluid outlet 128. The fluid inlet 126 is adapted to receive fluid from a non-illustrated fluid source. In the depicted embodiment the fluid inlet 126 is defined by the open top of fluid the fluid reservoir 106. It will be appreciated that this is merely exemplary, and that the fluid inlet 126 could be implemented via an opening formed through a side of the fluid reservoir 106, and that the fluid reservoir could be configured with a closed top.

Referring now to FIGS. 1-3 in combination, the piston 108 is movably disposed within the fluid reservoir 106, and is preferably disposed against the fluid reservoir inner surface 118. The piston 108 divides the fluid volume 122 into an upper variable fluid volume 132 and a lower variable fluid volume 134, and includes an upper side 136, a lower side 138, and an aperture 142 (shown more clearly in FIGS. 2 and 3). As is readily apparent, the upper side 136 is exposed to the upper variable fluid volume 132, the lower side 138 is exposed to the lower variable fluid volume 134, and the aperture 142 extends between the upper and lower sides 136, 138. As will be described in more detail further below, the piston 108 is movable between an uppermost position, which is the position depicted in FIG. 1, and a lowermost position. As illustrated more clearly in FIGS. 2 and 3, one or more seals 202 are preferably coupled to the piston 108. In the depicted embodiment, a cup seal 202 is used, though one or more other types of seals may be used.

The valve element 112 is disposed adjacent the piston 108 and is movable between a closed position, which is the position depicted in FIGS. 1 and 2, and an open position, which is the position depicted in FIG. 3. In the depicted embodiment, the valve element 112 is disposed adjacent to, and is selectively movable away from, the piston lower side 138. It will be appreciated, however, that this is merely exemplary and that the valve element 112 could, in some embodiments, be disposed adjacent to, and be selectively movable away from, the piston upper surface 136. In either case, when the valve element 112 is in the closed position it seals the piston aperture 142, thereby fluidly isolating the upper variable fluid volume 132 from the lower variable fluid volume 134. Conversely, when the valve element 112 is in an open position it does not seal the aperture 142, thereby fluidly communicating the upper variable fluid volume 132 with the lower variable fluid volume 134. In the depicted embodiment, and as shown most clearly in FIGS. 2 and 3, a valve seal 204 is preferably coupled to the valve element 112 to thereby improve the sealing capability of the valve element 112 when it is in the closed position.

The piston operator 114 is coupled to the piston 108 and is responsive to an input force to move the piston 108 between its uppermost and lowermost positions. Although the configuration of the piston operator 114 may vary, in the depicted embodiment, and as shown most clearly in FIGS. 2 and 3, the piston operator 114 is implemented as a hollow rod 206 having a lower end 208 and an upper end 148 (see FIG. 1). The lower end 208 is coupled to the piston 108, and more specifically to the piston upper surface 136, via a plurality of stanchions 212 and a mounting ring 213. The upper end 148 is coupled to the pump control 104, and more particularly to a piston actuator 152 that comprises the pump control 104. As depicted in FIG. 1, one or more support bearing assembly 153 (only one shown for clarity) may be included to provide lateral support for the piston operator 114. It will be appreciated that in alternative embodiments, the mounting ring 213 could be eliminated, and that the stanchions 212 may be configured in multiple ways.

The valve operator 116 is coupled to the valve element 112 and is operable to selectively move the valve element 112 between the closed position and an open position. Although the valve operator may also be variously configured, in the depicted embodiment the valve operator 116 is implemented as a shaft 214. The shaft 214 (see FIGS. 2 and 3) has a lower end 216 that is coupled to the valve element 112, and extends up through the hollow rod 206 to an upper end (not illustrated in FIGS. 1-3). The upper end is coupled to a valve actuator 154 that comprises the pump control 104. It will be appreciated that in alternative embodiments the valve operator 116 may be implemented using a cable rather than a shaft, or may be retained in the open position by mechanical means disposed on a face 220 or side 221 of the piston 108. Moreover, as depicted most clearly in FIG. 8, the valve operator 116 may be disposed external to the piston operator 114. In such embodiments, the piston operator 114 may, if so desired, be implemented as a solid rod rather than a hollow rod. As FIG. 8 also depicts, the valve operator 116 may be implemented, if needed or desired, using a plurality of shafts or cables one either one or both sides of the valve element 112.

Returning once again to FIG. 1, it is seen that a discharge conduit 156 is preferably coupled to the fluid reservoir 106. The discharge conduit 156 includes an inlet 155 and an outlet 162. The discharge conduit inlet 155 is in fluid communication with the lower variable fluid volume 134 via the fluid reservoir fluid outlet 128, and the discharge conduit outlet 162 disposed at a position above the upper variable fluid volume 132. To prevent, or at least inhibit, reverse flow back through the discharge conduit 156 and into the fluid reservoir 106, a check valve 164 is preferably disposed within the discharge conduit 156 between the discharge conduit inlet 158 and outlet 162.

The pump control 104, as has already been referred to, comprises the piston actuator 152 and the valve actuator 154. As FIG. 1 further depicts, the pump control 104 also preferably includes a valve actuator control 158. The piston actuator 152 is coupled to the piston operator 114, and more specifically to the hollow rod upper end 148. The piston actuator 152 is operable to selectively supply an input force to the piston operator 114 that moves the piston between the uppermost position and the lowermost position. The piston actuator 152 may be variously configured and implemented. For example, it may be a variously configured manually-operated actuator, a variously configured electromechanical actuator, a variously configured mechanical actuator, a variously configured hydraulic actuator, or a variously configured pneumatic actuator. In one particular preferred embodiment, the piston actuator is a hydraulic actuator.

The valve actuator 154 is coupled to the valve operator 116, and more specifically to the upper end of the shaft 214. The valve actuator 154, like the piston actuator 152, may be variously configured and implemented. For example, it may be a variously configured manually-operated actuator, a variously configured electromechanical actuator, a variously configured hydraulic actuator, a variously configured mechanical operator, or a variously configured pneumatic actuator. In one particular preferred embodiment, the valve actuator 154 is an electromechanical actuator, such as a solenoid actuator, that is coupled to receive actuator control signals. The valve actuator 154, in response to the actuator control signals, selectively supplies an actuation force to the valve operator 116 (e.g., the shaft 214) to move the valve element 112 between the closed position and an open position.

The valve actuator control 158 is coupled to, and supplies the actuator control signals to the valve actuator 154. As will be described momentarily, the valve actuator control 158 is configured to supply actuator control signals that cause the valve element 112 to be moved to the open position when the piston 108 is in the lowermost position, and cause the valve element 112 to be moved to the closed position when the piston 108 is in the uppermost position.

Turning now to FIGS. 4-7, the operation of the fluid pump 102, as implemented by the pump control 104 (not depicted in FIGS. 4-7), will now be described. Referring first to FIG. 4, the fluid pump 102 is depicted with the piston 108 disposed in the uppermost position, and with the valve element 112 in the closed position. Thereafter, the piston actuator 152 is controlled to supply an input force to the piston operator 114 that moves the piston 108 toward the lowermost position. Simultaneously, the valve actuator 154 is controlled to maintain the valve element 112 in the closed position. As the piston 108 moves downwardly, fluid 124 is discharged out of the lower variable fluid volume 134 and into and through the discharge conduit 156 and the check valve 164 until, as depicted in FIG. 5, the piston 108 reaches the lowermost position. Though not depicted in FIGS. 4 and 5, while fluid 124 is being discharged from the lower variable fluid volume 134, the upper variable fluid volume 132 is preferably being replenished with fluid 124 via, for example, the fluid inlet 126. The replenishing fluid 124, together with the fluid 124 initially in the upper variable fluid volume 132, provides additional force to move the piston 108 to the lowermost position.

As depicted in FIG. 6, when the piston 108 reaches the lowermost position, the valve actuator 154 is controlled to move the valve element 112 to an open position. Simultaneously, or at least substantially simultaneously, the piston actuator 152 is controlled to supply an input force to the piston operator 114 that moves the piston 108 back toward the uppermost position. When this occurs, fluid 124 in the upper variable fluid volume 132 flows through the aperture 142 and into the lower variable fluid volume 134. The piston actuator 152 continues to move the piston 108 upwardly, and the valve actuator 154 continues to maintain the valve element in the open position, as depicted in FIG. 7, until the piston 108 once again reaches the uppermost position. At that point, the pump control 104 reconfigures the fluid pump 102 to the configuration depicted in FIG. 4, and the pumping process repeats.

It is noted that the fluid pump 102 depicted and described herein is preferably configured such that the upper variable fluid volume 132 is always larger than the lower variable fluid volume 134, despite the position of the piston 108. This is because, as may be appreciated, a larger volume of fluid 124 above the piston 108 results in a greater gravitational force being applied to the piston 108. Hence, for a given input force from the piston operator 114, the height that the fluid 124 can be displaced from the fluid reservoir 106 as the piston moves downwardly is increased. Moreover, for a given height of fluid displacement from the fluid reservoir 106, the larger the volume of fluid 124 above the piston 108, the lower input force supplied from the piston operator 114 may be. As a result, a smaller, lower power piston operator may be used.

While at least one exemplary embodiment has been presented in the foregoing detailed description of the invention, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment of the invention. It being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the invention as set forth in the appended claims. 

1. A fluid pump, comprising: a fluid reservoir including an inner surface that defines a fluid volume for receiving a fluid; a piston movably disposed within the fluid reservoir against the inner surface and dividing the fluid volume into an upper variable fluid volume and a lower variable fluid volume, the piston movable between an uppermost position and a lowermost position and including an upper side exposed to the upper variable fluid volume, a lower side exposed to the lower variable fluid volume, and an aperture extending between the upper and lower sides; a valve element movable between a closed position, in which the valve element seals the aperture to thereby fluidly isolate the upper variable fluid volume from the lower variable fluid volume, and an open position, in which the valve element does not seal the aperture to thereby fluidly communicate the upper variable fluid volume with the lower variable fluid volume; a piston operator coupled to the piston, the piston operator responsive to an input force to move the piston to the uppermost position and the lowermost position; and a valve operator coupled to the valve element and operable to selectively move the valve element to the closed position and an open position.
 2. The pump of claim 1, further comprising: a piston actuator coupled to the piston operator and operable to selectively supply the input force thereto that moves the piston to the uppermost position and the lowermost position.
 3. The pump of claim 2, wherein: the piston operator comprises a rod coupled to the piston upper surface and extending upwardly therefrom to an upper end; and the piston actuator is coupled to the rod upper end.
 4. The pump of claim 3, further comprising: a support bearing assembly surrounding, and providing lateral support for, the rod.
 5. The pump of claim 3, wherein: the rod is hollow; and the valve operator comprises a shaft extending through the rod and having a lower end coupled to the valve element.
 6. The pump of claim 1, further comprising: a valve actuator coupled to the valve operator and operable to selectively supply an actuation force thereto that moves the valve element to the closed position and an open position.
 7. The pump of claim 1, further comprising: a discharge conduit having an inlet and an outlet, the discharge conduit inlet in fluid communication with the lower variable fluid volume, the discharge conduit outlet disposed at a position above the upper variable fluid volume.
 8. The pump of claim 7, further comprising: a check valve disposed within the discharge conduit between the discharge conduit inlet and outlet.
 9. The pump of claim 1, wherein the fluid reservoir includes a fluid inlet adapted to receive fluid from a fluid source.
 10. The pump of claim 1, wherein the upper variable fluid volume is larger than the lower variable fluid volume, regardless of the position of the piston.
 11. A fluid pump system, comprising: a fluid reservoir including an inner surface that defines a fluid volume for receiving a fluid; a piston movably disposed within the fluid reservoir against the inner surface and dividing the fluid volume into an upper variable fluid volume and a lower variable fluid volume, the piston movable between an uppermost position and a lowermost position and including an upper side exposed to the upper variable fluid volume, a lower side exposed to the lower variable fluid volume, and an aperture extending between the upper and lower sides; a valve element movable between a closed position, in which the valve element seals the aperture to thereby fluidly isolate the upper variable fluid volume from the lower variable fluid volume, and an open position, in which the valve element does not seal the aperture to thereby fluidly communicate the upper variable fluid volume with the lower variable fluid volume; a piston operator coupled to the piston, the piston operator responsive to an input force to move the piston to the uppermost position and the lowermost position; a valve operator coupled to the valve element and operable to selectively move the valve element to the closed position and an open position; a piston actuator coupled to the piston operator and operable to selectively supply the input force thereto that moves the piston to the uppermost position and the lowermost position; a valve actuator adapted to receive actuator control signals and operable, in response thereto, to selectively supply an actuation force to the valve operator to move the valve element to the closed position and an open position; and a valve actuator control operable to supply the actuator control signals to the valve actuator, the valve actuator control configured to supply actuator control signals that cause the valve element to be moved to (i) the open position when the piston is in the lowermost position and (ii) the closed position when the piston is in the uppermost position.
 12. The pump of claim 11, wherein: the piston operator comprises a rod coupled to the piston upper surface and extending upwardly therefrom to an upper end; and the piston actuator is coupled to the rod upper end.
 13. The pump of claim 12, further comprising: a support bearing assembly surrounding, and providing lateral support for, the rod.
 14. The pump of claim 12, wherein: the rod is hollow; and the valve operator comprises a shaft extending through the rod and having a lower end coupled to the valve element.
 15. The pump of claim 11, further comprising: a discharge conduit having an inlet and an outlet, the discharge conduit inlet in fluid communication with the lower variable fluid volume, the discharge conduit outlet disposed at a position above the upper variable fluid volume.
 16. The pump of claim 7, further comprising: a check valve disposed within the discharge conduit between the discharge conduit inlet and outlet.
 17. The pump of claim 1, wherein the fluid reservoir includes a fluid inlet adapted to receive fluid from a fluid source.
 18. The pump of claim 1, wherein the upper variable fluid volume is larger than the lower variable fluid volume, regardless of the position of the piston.
 19. A fluid pump, comprising: a fluid reservoir including a fluid inlet, a fluid outlet, and an inner surface that defines a fluid volume for receiving fluid; a piston movably disposed within the fluid reservoir against the inner surface and dividing the fluid volume into an upper variable fluid volume and a lower variable fluid volume, the piston movable between an uppermost position and a lowermost position and including an upper side exposed to the upper variable fluid volume, a lower side exposed to the lower variable fluid volume, and an aperture extending between the upper and lower sides; a valve element movable between a closed position, in which the valve element seals the aperture to thereby fluidly isolate the upper variable fluid volume from the lower variable fluid volume, and an open position, in which the valve element does not seal the aperture to thereby fluidly communicate the upper variable fluid volume with the lower variable fluid volume; a piston rod coupled to the piston upper surface and extending upwardly therefrom to an upper end, the piston rod responsive to an input force to move the piston to the uppermost position and the lowermost position; a valve operator coupled to the valve element; a piston actuator coupled to the piston rod and operable to selectively supply the input force thereto that moves the piston to the uppermost position and the lowermost position; a valve actuator coupled to the valve operator and operable to selectively supply an actuation force thereto that moves the valve element to the closed position and an open position; and a discharge conduit having an inlet and an outlet, the discharge conduit inlet in fluid communication with the lower variable fluid volume via the fluid reservoir fluid outlet, the discharge conduit outlet disposed at a position above the upper variable fluid volume.
 20. The pump of claim 19, further comprising: a check valve disposed within the discharge conduit between the discharge conduit inlet and outlet. 